1. Field of the Invention
The present invention relates to a power supply system, an electric vehicle and a charging adapter, and, in particular, to a technology that enhances convenience upon charging the electric vehicle.
2. Description of the Related Art
In recent years, electric vehicles that are equipped with an electric motor for propulsion have been under development. The electric vehicle is equipped with an electric storage device such as battery. Upon charging the electric storage device, an external power source and the electric vehicle are connected via a charging cable. Furthermore, in the field of hybrid electric vehicles that are equipped with an engine and an electric motor for propulsion, so called a plug-in type vehicle is under development whose electric storage device is charged with an external power source.
Since charging the electric storage device of the electric vehicle requires large electric power (for example, 1.5 kW to 40 kW), current passing upon charging may exceed a permissible current value of a charging facility, whereby a breaker may be activated. Thus, a charging system is developed that, in a facility where a plurality of electric vehicles can be charged, charges electric vehicles in a cooperative manner so that current does not exceed a permissible current value of the facility, preventing a breaker from being activated (see, for example, Japanese Unexamined Patent Application Publication No. 2003-333706).
In a typical household, an electric power line that is used for bringing in charging power is not prepared as a dedicated electric power line for charging an electric vehicle, but is often a common electric line that is also used for supplying electric power to other electric apparatuses. In the case where the electric power line that is used for bringing in charging power is such a common electric line also used for other electric apparatuses, it is necessary to restrict the use of other electric apparatuses when the electric storage device is charged so as to prevent an activation of a breaker due to excess current. However, since charging of the electric storage device is continued for a long period of time, restricting the use of other electric apparatuses upon charging the electric storage device significantly impairs user's convenience.